METHOD AND DEVICE FOR DEZINCIFICATION OF PELLET

PURPOSE:To minimize the generation of iron dust during calcining and to recover vaporized zinc efficiently, by using a heating system using moving beds for calcining the green pellets of dust generated from iron works and separating the iron powder and zinc in gaseous atmospheres. CONSTITUTION:The green pellets 3 supplied from a chute 4 are arrayed in specified layer thickness on a moving bed 1 by a feeder 5, and are transferred in a substantially static state. When the pellets enter the heating zone formed with burners 2, the green pellets are first dehydrated and preheated in a low temp. part and in succession, the pellets are heated to high temp. in a high temp. part so that the Zn existing in the form of ZnO is reduced and evaporated, then the evaporation of metallic zinc takes place. The iron powder and zinc vapor generated in the heating zone during this time are sucked together with gaseous atmospheres with a hood 6 and a duct 7. The velocity of flow is increased with a venturi 9 in the mid-way of the duct to cool the dust and vapor quickly and at the same time, to force the same to collide againt a sepn. plate 10. Then, the iron powder is separated of the zinc stuck on the surfaces thereof and is recovered into a bucket 11 and the zinc dust is recovered in high concn. into a bag filter 12.